Lactation

Question 1

Advantages of breastfeeding, for infant (3)

Answer 1

• Confers immunologic protection for the child
• Nutritional composition tailored to nutritional needs of human infant
• Neurodevelopmental benefits
  
  • Bonding and increased cognitive performance (data controversial(

Question 2

Immunologic protections conferred by breastfeeding

Answer 2

• Acute infections
  
  • GI infection - ↓ 64%
  • Lower respiratory infection - ↓ 72%
  • Acute otitis media - ↓ 50%
• Chronic conditions
  
  • Asthma - ↓ 27%
  • Obesity - ↓ 24%
  • Type 2 DM - ↓ 39%
  • Leukemia - ↓ 19%

Question 3

Nutritional composition of breastmilk & advantages for child

Answer 3

• Macronutrient and micronutrient balance
  
  • High fat content –> efficient weight gain
  • Low renal solute load beneficial for immature kidneys
  • Modest protein content (primarily whey, 60%)
    
    • Enhances mineral absorption
  • Presence of long-chain polyunsaturated fatty acids (omega-3’s)
    
    • Good for baby’s brain development
  • High lactose
• All components present in amounts that provide adequate intake to baby while minimizing demand on mother

Question 4

Advantages of breastfeeding, for mother

Answer 4

• Prevention of post-partum hemorrhage
  
  • Oxytocin stimulates uterine contraction
• Weight loss
  
  • Average return to pre-pregnancy weight after approx. 6mo of lactation
  • Lower rates of obesity associated with breastfeeding - suggesting protective effect
• Lactational amenorrhea/birth spacing - free birth control
  
  • Also spares nutrients, especially iron
  • BF > 6 months associated with increased inter-pregnancy interval to one year
  • Provides > 98% protection from pregnancy of about 6 months, if exclusively breastfeeding
  • Requires frequent nursing episodes with intervals < 5 hours
• Reduced risk of osteoporosis, breast, and ovarian cancer
• Bonding/stress reduction
  
  • Associated with decreased steroid hormones in breastfeeding women
• Economic benefit
  
  • Savings in medical expenses & not buying formula or pumps

Question 5

Nutritional composition of breast milk

Answer 5

• Fat
  
  • Total: 4.2 g/100mL
  • trace fatty acids
  • 14% polyunsaturated fatty acids
• Protein
  
  • Total: 1.1 g/100mL
  • Casein 0.3g/100mL
  • a-lactalbumin: 0.3g/100mL
  • Lactoferrin: 0.2g/100mL
  • IgA: 0.1 g/100mL
  • IgG: 0.001 g/100mL
  • Lysozyme: 0.05
  • Serum albumin: 0.05
• Carbohydrate
  
  • Lactose: 7g/100mL
  • Oligosaccharides: 0.5g/100mL
• Minerals
  
  • Calcium: 0.03g/100mL
  • Phosphorus: 0.014g/100mL
  • Sodium: 0.015g/100mL
  • Potassium: 0.055g/100mL
  • Chlorine: 0.043g/100mL

Question 6

Impact of maternal diet on nutritional composition of breastmilk

Answer 6

• Maternal malnutrition –> reduced milk supply
  
  • But minimally altered macronutrient and mineral content
    
    • Exceptions: selenium & iodine
• Maternal diet does affect content of vitamins in human milk
• In adequately nourished women, additional energy and fluid intake does not affect volume

Question 7

Immune factors in human milk

Answer 7

• Lactoferrin
  
  • Bacteriostatic effect by binding iron
• Secretory IgA
  
  • Mucosal protection
• Oligosaccharides and glycoproteins
  
  • Prevent attachment of pathogenic agents to epithelial lining of mucosal surfaces by encouraging growth of non-pathogenic flora
• Immune cells including macrophages

Question 8

Recommendations for breastfeeding (WHO & AAP)

Answer 8

• Exclusive breastfeeding for 6 months
• Continue to breastfeeding through:
  
  • 1 year of life (AAP)
  • 2 years of life (WHO)
• With appropriate complementary feeding initiated at 6 months

Question 9

Recommendations for breastfeeding for women with HIV

Answer 9

• WHO, 2009: Women and infants should receive antiretroviral therapy (ART) and breastfeed for 12 months
• If ART not available, carefully consider alternatives to breastfeeding (formula, wet nurse)
• CDC: HIV-infected women in US should not breastfeed infants

Question 10

U.S. Healthy People 2020 Goals for breastfeeding

Answer 10

• Don’t worry about specific numbers
• Increase proportion of infants who are breastfed; targets:
  
  • 81.9% “ever breastfed” initiation rates
  • 60.6% at 6 months
  • 34.1% continue breastfeeding at 1 year
  • Goals for exclusive BF at 3 months = 46.2%, 25.5% at 6 months
• Increase proportion of employers with worksite lactation support programs 25% –> 38%
• Decrease proportion of breastfed newborns who receive formula supplementation within first 2 days of life 25% –> 10%
• Increase proportion of live births in facilities that provide recommended care for lactating women and infants 4 –> 8.1%

Question 11

10 steps to improve breastfeeding encouragement in hospitals

Answer 11

1. Maintain written breastfeeding policy that is routinely communicated to all healthcare staff
2. Train all healthcare staff in skills necessary to implement this policy
3. Inform all pregnant women about benefits and management of breastfeeding
4. Help mothers initiate breastfeeding within 30 minutes - 1 hour of birth
5. Show mothers how to breastfeed and how to maintain lactation, even if separated from infants
6. Give infants no food or drink other than breast milk unless medically indicated
7. Practice rooming in - allow mothers and infants to remain together 24 hours/day
8. Encourage unrestricted breastfeeding
9. Give no pacifiers or artificial nipples to breastfeeding infants
10. Foster establishment of breastfeeding support groups & refer mothers to them on discharge from hospital/clinic

Question 12

Biggest barrier to encouraging breastfeeding in US hospitals

Answer 12

• Acceptance of free formula from pharmaceutical companies

Question 13

Socioeconomic and cultural factors influencing breastfeeding in US

Answer 13

• Who breastfeeds in US?
  
  • Women who are older (> 24 years)
  • More highly educated
  • Employed part-time or not employed
  • Not participating in WIC
  • Live in New England, Mountain, or Pacific regions
  • Caucasians and Hispanics tend to breastfeed more than Blacks

Question 14

Reasons for recommending breastfeeding within 1 hour of birth

Answer 14

• Infants placed on abdomen that self-attach to breast and nurse within 1 hour have better breastfeeding outcomes
  
  • Increased number who continue breastfeeding 2-4months post partum
• Skin-to-skin contact in delivery room helps baby maintain body temp
• Infant typically alert & active for about 1 hour after delivery, then increased sleepiness
• Can be achieved by delaying routine procedures as possible:
  
  • Weighing, vitamin K shot, eye prophylaxis

Question 15

Hospital practices with a negative impact on breastfeeding

Answer 15

• Mother-infant separation at birth
• Mother-infant housed on separate floors
• Mother encouraged to “get your rest,” “take it easy,” or discouraged from breastfeeding
• Pictures of bottle feeding
• Formula feeding in nurseries
• Discharge packs with formula kit

Question 16

Physiologic adaptations to extra-uterine life by newborn

Answer 16

• Glycogen stored in utero is utilized for first 12 hours
• Low blood glucose of 40-50 mg/dL –> decreased insulin + increased glucagon –> gluconeogenesis
• Utilization of fat stores
  
  • Brown and white fat provide substrate for energy production
  • Glucagon –> increased adipose tissue hormone sensitive lipase –> oxidation of fatty acids + glycerol –> glucose

Question 17

Early pattern of weight loss and regain by baby

Answer 17

• Decrease in weight for first 2-4 days is normal and occurs via diuresis
• Weight loss should not continue once mother’s milk comes in
• Weight loss > 7% may indicate inadequate milk intake
• By day 4-5, should start gaining weight (15-30g/day)
• Birth weight should be re-achieved by day 7-10
• Formula fed infants generally don’t have same degree of weight loss

Question 18

Considerations related to recent findings of risk for traditional infant formulas

Answer 18

• Suggest intact cow milk protein may cause increased risk of atopic disease (eczema, asthma, allergy)
• May be a benefit of partially hydrolyzed cow milk protein for prevention of atopic disease, but can be 3x more expensive
• Have to consider if human milk with IgA is preventing these diseases, if cow milk is causing them, or what really is going on (not clear yet)

Question 19

Rationale/approach for development of WHO growth standards, compared to US/CDC growth references

Answer 19

• WHO growth standards:
  
  • Based on 6 country longitudinal study of infant growth from 0-24 months
  • Infants who were fed according to current recommendations (exclusive breastfeeding x 6 months)
  • Continued breastfeeding through 1 year
  • Appropriate complementary foods introduced by 6 months
  • No food insecurity
  • (+) medical care
• US adopted WHO growth standards in September of 2010 - does not use CDC charts anymore
• Findings:
  
  • Minimal difference in linear growth among 6 different sites
  • Slower weight gain compared to formula-fed infants
  • Normal development/achievement of motor milestones
  • With WHO charts, fewer BFI will appear to have growth faltering after 6 months of age